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Illuminated light switches and flourescent lights

Just back from the break. Spent some time doing odd jobs around the house. We use the compact fluorescent light bulbs around the house, I'd noticed one of them flickering when it was supposed to be switched off. The reason dawned on me when I was thinking about the illuminated switch that controls that particular light.

I started thinking about where the power to make the switch glow came from, after a moment of reflection it was clear that there had to be a small current flowing in order for the switch to light up. And if there's a small current flowing through the switch, then there has to be one flowing through the fluorescent bulb, presumably just enough to make it flicker.

I found a blog entry which confirmed this, plus showed some nice illustrations.

Unfortunately there are only two solutions. (1) Don't use illuminated switches or (2) Don't use fluorescent lights.

About

Darryl Gove is a senior engineer in the Solaris Studio team, working on optimising applications and benchmarks for current and future processors. He is also the author of the books:Multicore Application ProgrammingSolaris Application ProgrammingThe Developer's EdgeFree Download